Research on effects of fertilization with mulching on water and nitrogen use efficiency in the field and maize yield is of great significance to increasing crop yield. For better understanding the effects of drip fertigation with straw mulching on water and nitrogen use efficiency under heat conditions in the field and summer maize yield in semi-humid regions

field experiments were carried out in Daxing district of Beijing city

China

during the growing seasons of summer maize in 2014 and 2015. In the experiments

six treatments

including no fertilization with straw mulching (T1)

no fertilization without straw mulching (T2)

middle fertilization with straw mulching (T3)

middle fertilization without straw mulching (T4)

high fertilization with straw mulching (T5)

and high fertilization without straw mulching (T6) were tested. The results showed that: surface soil temperature and air temperature had a high linear correlation

and straw mulching could reduce soil warming rate during the growing season of summer maize. Compared with that in T2

T4 and T6

soil warming rate in T1

T3 and T5 decreased by 23.62%

13.65% and 11.47%

respectively. During the whole growing season

average daily soil temperature in treatments with straw mulching was 1.75 ℃ lower than that in treatments without straw mulching. Under drip irrigation

straw mulching could affect the distribution of soil moisture in the 0—60 cm soil layer

especially for soil moisture content of the 0—20 cm soil layer. In 2014

average soil water content was increased by 11.73%

and the average increase was 9.56% in 2015. In treatments with straw mulching

E/ET was decreased by 6.99% on average when compared with treatments without straw mulching

and water consumption of summer maize was the highest from the heading to grain-filling stage. The results indicated that T3 had the highest grain yield

being 27.62% higher compared with that of T2

and 15.83% higher than that of T6

T3 also showed optimal water use efficiency and fertilizer partial productivity

which was 23.73 kg/（hm2·mm）and 40.33 kg/kg

respectively. In conclusion

middle fertilization with straw mulching can reduce soil warming rate under drip irrigation

it can increase maize yield and at the same time show optimal water use efficiency and fertilizer partial productivity.